Background/Aims: 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) has been suggested as a reliable imaging technique for monitoring of disease activity in patients with adult-onset Still's disease (AOSD). Therefore, we investigated the clinical significance of 18F-FDG PET/CT in Korean AOSD patients. Methods: Thirteen AOSD patients were included in the study. The PET/CT images were evaluated with visual and semiquantitative method using standardized uptake values (SUVs)...

BACKGROUND: A major obstacle in using FDG-PET/CT to diagnose cardiac sarcoidosis (CS) is the unpredictable physiological myocardial FDG uptake. We hypothesized that a prolonged 72-hour pretest high-fat, high-protein, and very-low-carbohydrate (HFHPVLC) diet preparation could suppress physiologic myocardial uptake of FDG and thus help to identify active CS. METHODS: This retrospective study included 215 FDG-PET/CT tests from 207 patients with biopsy-proven sarcoidosis and clinical suspicion for CS between July 2014 and December 2015...

OBJECTIVE: Patients presenting with cystic lesions in the neck without obvious signs of malignancy constitute a diagnostic challenge since fine needle aspiration is often insufficient and a diagnosis may not be reached until surgical resection/biopsy is performed. The differential diagnosis of a cystic cervical mass comprises a variety of benign conditions, but malignancy must be ruled out. We examined the diagnostic performance of fluorine-18 fluorodeoxyglucose ((18)F-FDG) PET/CT to identify malignancy...

Positron emission tomography (PET) images are potential quantitative biomarkers. Understanding long-term (months/years) biomarker variability is important for establishing confidence intervals on studies using such biomarkers over these time frames. PET biomarkers are derived from activity concentration ([Formula: see text]) extracted from PET images. Over 30 months, we measured the stability of decay-normalized counts ([Formula: see text]) and [Formula: see text] by scanning the same 4.5-cm-diameter Ge-68 cylinder weekly, the same Na-22 point source daily, and a refilled 20-cm F-18 cylinder phantom monthly on a clinical TOF-PET/CT scanner...

The ontogenesis of the nasal cavity has been described in many mammalian species. The situation is different with reptiles, despite the fact that they have become relatively common as pets. In this study we focused on the ontogenesis of the olfactory epithelium, as well as other types of epithelia in the nasal cavity of pre-hatched green iguanas (Iguana iguana). Collection of samples began from day 67 of incubation and continued every four days until hatching. Microscopic examination revealed that significant morphological changes in the nasal cavity began approximately at day 91 of ontogenesis...

Choline is a new positron emission tomography (PET) tracer useful for detection of prostate cancer and metastatic lesions. We report a 70-year-old man with prostate cancer and multiple abdominal, pelvic, and inguinal node metastases. PET scans demonstrated accumulation of (11)C-choline in the primary tumor and lymph node metastases but no accumulation of (18)F-FDG. Choline PET/computed tomography may be useful for diagnosis of advanced prostate cancer with suspected metastatic lesions and treatment planning...

PET/MR is an emerging hybrid imaging modality. However, attenuation correction (AC) remains challenging for hybrid PET/MR in generating accurate PET images. Segmentation-based methods on special MR sequences are most widely recommended by vendors. However, their accuracy is usually not high. Individual refinement of available certified attenuation maps may be helpful for further clinical applications. In this study, we proposed a multi-resolution regional learning (MRRL) scheme to utilize the internal consistency of the patient data...

OBJECTIVE: With the advent of regenerative/cell therapy for Parkinson's disease (PD), (18)F-FDOPA has drawn new attention as a biomarker of the therapeutic that cannot be evaluated with radiopharmaceuticals for dopamine transporter. Since most previous (18)F-FDOPA PET studies were carried out many years ago with a PET scanner of lower resolution and with (18)F-FDOPA of low specific activity synthesized from (18)F-F2, we used a newer PET/CT scanner with a high-resolution condition and (18)F-FDOPA synthesized from (18)F-F(-) to re-evaluate this technique on normal subjects and patients with PD, together with D2 receptor imaging with (11)C-raclopride (RAC)...

BACKGROUND: To this day the definite diagnosis of Alzheimer's disease still relies on post-mortem histopathological detection of neurofibrillary tangles and beta-amyloid deposits. Amyloid positron emission tomography (PET) is a new diagnostic tool that enables the in vivo quantification of pathological beta-amyloid deposits. The aim of the current study was to evaluate to what extent (18)F-florbetaben-PET (FBB-PET) influences the diagnosis of patients with dementia. MATERIAL AND METHODS: Imaging with FBB-PET was performed on 33 patients from our outpatient department for cognitive neurology...

Treating Hodgkin lymphoma by using chemotherapy with or without radiotherapy is highly successful, with substantially fewer deaths from lymphoma than from other causes in recent studies of both early-stage and advanced-stage disease. Long-term toxicity is a major consideration in this context, and recent trials have used functional imaging with [(18)F]fluorodeoxyglucose (FDG) positron emission tomography early in the course of treatment (interim PET) to assess response and modulate subsequent therapy. In early-stage disease, this has allowed omission of consolidation radiotherapy after a good response to doxorubicin, bleomycin, vinblastine, and dacarbazine (ABVD) chemotherapy, and trials have shown that this can be done without detriment to overall survival, despite a small increase in rates of recurrence of ∼5%...

BACKGROUND: There are few data to support the use of varying imaging modalities in evaluating recurrence in non-small-cell lung cancer (NSCLC). We compared the efficacy of surveillance positron emission tomography (PET)/computed tomography (CT) versus CT scans of the chest in detecting recurrences after definitive radiation for NSCLC. MATERIALS AND METHODS: We retrospectively analyzed 200 patients treated between 2000 and 2011 who met the inclusion criteria of stage III NSCLC, completion of definitive radiation treatment, and absence of recurrence within the initial 6 months...

A reliable method for the diagnosis of minimal cardiac ischemia would meet a strong demand for the sensitive diagnosis of coronary artery disease in cardiac stress testing and risk stratification in patients with chest pain but unremarkable ECGs and biomarkers. We hypothesized that platelets accumulate early on in ischemic myocardium and a newly developed technology of non-invasive molecular PET imaging of activated platelets can thus detect minimal degrees of myocardial ischemia. To induce different degrees of minimal cardiac ischemia, the left anterior descending artery (LAD) was ligated for 10, 20 or 60 min...

A 68-year-old man was referred to our hospital because of an abnormal shadow in the chest roentgenogram. Chest computed tomography (CT) showed the nodule in the right upper lobe (S3), 17 mm in size. One month later, fluorodeoxyglucose-positron emission tomography (FDG-PET)/CT scanning revealed positive reaction in the right upper lobe lesion and new lesion close to another lobe. In addition, interloblar small nodules were detected, 5 mm and 7 mm in size. A transbronchial brush cytology by bronchoscopy was performed, and the microscopic findings demonstrated the presence of atypical cells, suspected adenocarcinoma...

PURPOSE: Several studies outlined the sensitivity of (68)Ga-labeled PET tracers against the prostate-specific membrane antigen (PSMA) for localization of relapsed prostate cancer in patients with renewed increase in the prostate-specific antigen (PSA), commonly referred to as biochemical recurrence. Labeling of PSMA tracers with (18)F offers numerous advantages, including improved image resolution, longer half-life and increased production yields. The aim of this study was to assess the PSA-stratified performance of the (18)F-labeled PSMA tracer (18)F-DCFPyL and the (68)Ga-labeled reference (68)Ga-PSMA-HBED-CC...

PURPOSE: CT images are used for patient specific Monte Carlo treatment planning in radionuclide therapy. The authors investigated the impact of tissue classification, CT image segmentation, and CT errors on Monte Carlo calculated absorbed dose estimates in nuclear medicine. METHODS: CT errors as a function of patient size, CT reconstruction, and tube current modulation methods were assessed in a phantom experiment on a clinical CT system. The impact of tissue segmentation methods and CT number variations on EGSnrc Monte Carlo calculated absorbed dose distributions was assessed for (99m)Tc and (131)I in the ICRP/ICRU male phantom and in a patient PET/CT-scanned with (124)I prior to radioiodine therapy...

INTRODUCTION: The commercially available (68)Ge/(68)Ga generators are generally used in clinical context in conjunction with automated or semi-automated modules for the syntheses of (68)Ga radiopharmaceuticals. It is desirable to develop strategies for the formulation of (68)Ga-radiopharmaceuticals without use of such expensive modules in order to make (68)Ga-based clinical positron emission tomography (PET) more popular and affordable worldwide. METHODS: An organic matrix based (68)Ge/(68)Ga generator was used for preparation of clinically relevant doses of four different (68)Ga-based radiopharmaceuticals, namely (68)Ga-DOTA-NOC, (68)Ga-NODAGA-RGD2, (68)Ga-PSMA-11 and (68)Ga-BPAMD...

OBJECTIVES: Considering the fact that the standardized uptake value (SUV) of a normal lung tissue is expressed as x±SD, x+3×SD could be considered as the threshold value to outline the internal tumor volume (ITV) of a lung neoplasm. METHODS: Three hollow models were filled with 55.0 kBq/mL fluorine-18 fluorodeoxyglucose ((18)F-FDG) to represent tumors. The models were fixed to a barrel filled with 5.9 kBq/mL (18)F-FDG to characterize normal lung tissues as a phantom...

OBJECTIVES: In clinical practice, approximately 10-25% of post-surgical differentiated thyroid carcinoma (DTC) patients with high serum thyroglobulin (Tg) and negative (131)I whole-body scan (WBS) have poor prognosis due to recurrent or metastatic lesions after radioactive iodine treatment. The purpose of this study was to evaluate the value of (18)F-FDG PET/CT scan in DTC patients with high serum Tg level and negative (131)I WBS. METHODS: 69 post-surgical DTC patients with high serum Tg level and negative post ablation (131)I WBS were enrolled in this study...